Re: PHP One or many files?
there's a number of ways you can go about this...
one is to have individual files for everything and each file is all inclusive with a header, nave and footer and all that.
Another method is to slice up the page and included bits as needed. so you have an index.php (home), gallery.php, header.php, nav.php, footer.php... your index and gallery would then include header, footer and nav in the correct locations...
Another method is to have a single index.php, and then content files, home, gallery, etc... your links would then look like index.php?p=gallery and then you would include the proper content file as needed...
Yet another option is to go with AJAX, and dynamically load content into a div container... this is much like the previous option with the exception that there wouldn't be a page load...
Any yet ANOTHER option is to go with a model framework like MVC that allows you to define different views & data and can be template driven... this takes a bit more work and forethought to put together.
I'm sure there's other options, and probably options that are a combination of several of those options...
-tg